276142 - XUL scrollbar element does not work correctly on Mac

Status: NEW

(Core :: XUL, defect)

Description

[bugs]

XUL scrollbar elements do not have the correct functionality on Mac.  Scrollbar
elements display correctly but they do not fire oncommand events nor does the
thumb position correctly, either by dragging or click the increment/decrement
buttons.

Comment 1

[bugs]

Attachment: Example of the problem

The example page attached use a scrollbar element directly from xulplanet.

Comment 2

[bugs]

Normally I try to fix these types of bugs in the associated XBL.  In this
particular case I can not find anywhere in the chrome css (any of them) where
the scrollbar.xml#scrollbar binding is actually bound to scrollbar elements. If
someone could point me in the right direction I would be happy to try and
resolve this myself.

Comment 3

[Boris Zbarsky [:bzbarsky]]

Neil, any idea?

Comment 4

[[e-mail]]

I wasn't aware that scrollbars are supposed to fire command events, although the
scrollbarbuttons may do but only because they are buttons. Additionally, the Mac
Classic theme handles scrollbars natively, although there is some XBL glue, see:
http://lxr.mozilla.org/seamonkey/source/xpfe/global/resources/content/bindings/nativescrollbar.xml

Comment 5

[bugs]

Only the buttons fire oncommand events, and only in windows.  All platforms
should  operate the same, either fire the events or not.  Also what event if any
should be fired when the thumb position is changed? Not alot of use as a stand
alone widget with out an event.

Comment 6

[Marco Perez [:mpk]]

Confirming for FreeBSD, where the buttons fire 'oncommand' events, too.
You may use 'ondraggesture' to fire events dragging the scrollbar thumb
(and of course 'onclick' to fire when clicking on the scrollbar tray).
Shouldn't 'oncommand' fire in all those three cases?

Comment 7

[[e-mail]]

Unfortunately we don't have a proper scrollbar API. As far as it goes the only
currently correct way to use a scrollbar is to inspect the curpos attribute.